1. Field of the Invention
The present invention relates to a copper alloy and a method for manufacturing the same.
2. Description of Related Art
Heretofore, as a copper alloy used for wires, a Cu—Zr-based alloy has been known. For example, according to Patent Literature 1, a copper alloy wire having improved electrical conductivity and tensile strength has been proposed. This copper alloy wire is obtained in such a way that after a solution treatment is performed on an alloy containing 0.01 to 0.50 percent by weight of Zr, wire drawing thereof is performed to obtain a wire having a final wire diameter, and a predetermined aging treatment is then performed. In this copper alloy wire, Cu3Zr is precipitated in a Cu mother phase so that the strength is increased to 730 MPa. In addition, according to Patent Literature 2, the present inventors have proposed that in order to increase the strength to 1,250 MPa, a copper alloy is formed which contains 0.05 to 8.0 atomic percent of Zr, which includes a Cu mother phase and a eutectic phase of Cu and a Cu—Zr compound, each phase having a layered structure, and which has a biphasic structure in which adjacent crystal grains of the Cu mother phase are intermittently connected to each other. In addition, for example, there have also been proposed a copper alloy wire which includes a copper mother phase and a composite phase formed of a copper-zirconium compound phase and a copper phase and which forms a mother phase-composite phase fibrous structure from the copper mother phase and the composite phase (for example, see Patent Literature 3) and copper alloy foil which includes a copper mother phase and a composite phase formed of a copper-zirconium compound phase and a copper phase and which forms a mother phase-composite phase layered structure from the copper mother phase and the composite phase (for example, see Patent Literature 4). Since the copper alloy described above is formed to have a dense fibrous or a dense layered dual structure, the tensile strength thereof can be increased.
PTL 1: JP 2000-160311 A
PTL 2: JP 2005-281757 A
PTL 3: WO2011/030898
PTL 4: WO2011/030899